CVE-2019-12331

PHPOffice PhpSpreadsheet before 1.8.0 has an XXE issue. The XmlScanner decodes the sheet1.xml from an .xlsx to utf-8 if something else than UTF-8 is declared in the header. This was a security measurement to prevent CVE-2018-19277 but the fix is not sufficient. By double-encoding the the xml payload to utf-7 it is possible to bypass the check for the string ‚<!ENTITY‘ and thus allowing for an xml external entity processing (XXE) attack.

CVSS v3.0 8.8 HIGH
CVSS v2.0 6.8 MEDIUM

8.8^/10

CVSS v3.0 : HIGH

V3 Legend

Vector :

Exploitability : 2.8 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

6.8^/10

CVSS v2.0 : MEDIUM

V2 Legend

Vector : AV:N/AC:M/Au:N/C:P/I:P/A:P

Exploitability : 8.6 / Impact : 6.4

Access Vector NETWORK

Access Complexity MEDIUM

Authentication NONE

Confidentiality Impact PARTIAL

Integrity Impact PARTIAL

Availability Impact PARTIAL

References

Link	Resource
https://herolab.usd.de/security-advisories/usd-2019-0046/	Exploit Third Party Advisory
https://github.com/PHPOffice/PhpSpreadsheet/blob/master/CHANGELOG.md#180---2019-07-01	Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:phpspreadsheet_project:phpspreadsheet:*:*:*:*:*:*:*:*

Information

Published : 2019-11-07 07:15

Updated : 2020-02-10 13:49

NVD link : CVE-2019-12331

Mitre link : CVE-2019-12331

JSON object : View

CWE

CWE-611

Improper Restriction of XML External Entity Reference

Products Affected

phpspreadsheet_project

phpspreadsheet

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8.8 /10